Lubricating arrangement for the starter motor of an internal combustion engine



Aug. 7, 1956 w. G. STEGEMANN 2,757,656 LUBRICATING ARRANGEMENT FOR THE STARTER MOTOR OF AN INTERNAL COMBUSTION ENGINE Filed June 3, 1954 INVENTOR Wea er 6. Sfeyem 0 United States Patent LUBRICATING ARRANGEMENT FOR THE STARTER MOTOROF AN INTERNAL COM- BUSTION ENGINE Werner G. Stegemann, Pinneherg, Germany, assignor to Heinrich Ch. Christiansen, Wedel, Holstein, Germany Application June 3, 1954, Serial No. 434,227 Claims priority, application Germany June 8, 1953 4 Claims. (Cl. 123-496) Larger size internal combustion engines, especially diesel engines are generally equipped with a special motor for starting the engine. Preferably an Otto-motor is selected as starting motor in this connection.

Lubricating arrangements for the starter motor of an internal combustion engine as they have been known heretofore require special servicing and operation of such starter motor and furthermore require special proportioning of fuel and oil if the starter motor requires a pure oil mixture as fuel.

It is, therefore, an object of the present invention to provide a lubricating arrangement which will overcome the above mentioned drawbacks.

It is another object of this invention to provide a lubricating arrangement for the starter motor of an internal combustion engine which will be highly reliable and will not require special operation and servicing.

These and other objects and advantages of the invention will appear more clearly from the following specification in connection with the accompanying drawing in which:

Fig. 1 illustrates an embodiment of the invention in which a two-stroke Otto-motor requiring a fuel-oil mixture is used as starter motor.

Fig. 2 illustrates a slightly modified arrangement for use in connection with a starter motor operated by fuel only, in other words a starter motor which does not require a fuel-oil mixture.

General arrangement More specifically the present invention concerns a lubricating arrangement for the starter motor of an internal combustion engine, in which the lubricating system for the starter motor is connected to the lubricating system for the internal combustion engine which may henceforth be called the main motor. The arrangement according to the present invention, is characterized in that the lubricating pump for the starting motor withdraws the lubricating oil required for the starter motor from a container which is fed by the lubricating system of the internal combustion engine or main motor and which holds the quantity of lubricating oil required for the starter motor, even if the main motor is at a standstill. Due to this arrangement, the required feeding of the starter motor with lubricating oil, which feeding is always required for a short time only, is assured to a satisfactory extent. Furthermore, the operator who has to attend to the main motor can now devote his undivided attention to the latter and does not have to bother with the lubrication of the starter motor. According to the invention, the lubrication of the starter or auxiliary motor is completely independent of any servicing or attendance by the operator. This is of particular advantage when as starter motor a two-stroke cycle Ottomotor is selected which has to be supplied with a mixture of fuel and lubricating oil, with the fuel and oil intermixed at a certain ratio. Thus, while heretofore, whenever a starter motor was employed requiring a certain mixture of fuel and lubricating oil, such mixture had to be carefully prepared, this mixing operation is completely eliminated I 2,757,65ii Patented Aug. 7, 1956 invention is also of great importance if a four-stroke cycle Otto-motor is used as starting motor.

The connection of the lubricating system for the starter motor with the lubricating system of the main motor may be effected in diiferent manners. Thus, the lubricating oil to be supplied to the oil container or reservoir for the starter motor may be passed under pressure to said reservoir through a pipe system which branches off from the lubricating system for the main motor. The said pressure is produced by the lubricating pump associated with the main motor. The said oil container or reservoir is preferably independent of the oil sump in the crankcase of the main motor and communicates with a feeding conduit in which the oil stands under the pressure of the lubricating oil feeding pump of the main motor. The said reservoir is arranged as overflow container in the crankcase of said main motor so that the excessive quantity of oil can pass back into the lubricating oil circuit of the main motor. This is highly advantageous in view of the fact that only a small quantity of oil is required for the starter motor.

If a two-stroke cycle Otto-motor is used as starter motor, the lubricating oil pump pertaining to the starter motor may be so adjusted that the lubricating oil will be passed into the oilfeeding circuit of the starter motor at a point following the'carburetor. If the starter motor does not require a fuel-oil mixture, the lubricating oil may be passed directly to the lubricating points of the starter motor.

Structural arrangement Referring now to the drawing in detail and Fig. 1 thereof in particular, the arrangement shown therein comprises an internal combustion engine or main motor 1 the flywheel of which is provided with a toothed rim 2. The drive shaft 5 of the starter motor 4 which is assumed to be a two-stroke cycle Otto-motor requiring a mixture of fuel and lubricating oil is adapted through the intervention of a detachable clutch (not shown in the drawing) to drive a spur gear 3 which meshes with the toothed rim 2 for rotating the fly-wheel. A conduit 7 branches otf from the lubricating oil system 6 of the main motor. The oil in said system 6 stands under the pressure produced by the oil pump pertaining to the main motor. The purpose of the conduit 7 consists in feeding a small quantity of oil into an open container or reservoir 8 which is arranged inside the crankcase 9 of the main motor. From the reservoir 8 there passes a conduit 10 to the lubricating oil pump 11 of the starter motor. It will be appreciated that during the operation of the starter motor, the pump 11 draws lubricating oil from the reservoir 8 through the conduit 10.

If the starter motor 4 is to be fed with a fuel-oil mixture, thepump 11 feeds lubricating oil through the pressure conduit 12 into the feeding line of the starter motor at a point which is located past the carburetor 13.

If the starter motor 4 is to be operated with fuel only, i. e. without admixture of oil, the oil feeding system for the starter motor 4 is modified in conformity with the showing of Fig. 2 according to which the pump 11 feeds lubricating oil through conduit 14 directly to the lubricating points of the starter motor 4.

It will be appreciated that in both instances the starter motor is to be supplied with fuel from a fuel tan}: 15. The

3 excess oil fed into the reservoir 8 Will flow over the upper edges thereof and return to the oil sump of the crankcase 9, thereby returning to the lubricating circuit of the main motor.

It is, of course, understood that the present invention is, by no means, limited to the particular constructions shown in the drawing but also comprises any modifications within the scope of the appended claims.

What I claim is:

1. In combination with an internal combustion engine having a lubricating oil feeding system therefor including an oil sump: a starter motor arranged for selective driving connection with said internal combustion engine to start the latter, an oil reservoir separate from said oil sump and arranged to be fed with oil by said oil feeding system, conduit means communicating with said reservoir and arrangcdto convey oil from said reservoir to said starter motor, and oil pump means provided in said conduit means and arranged to feed oil from said reservoir to said starter motor independently of a flow of lubricating oil through said lubricating oil feeding system.

2. In combination with an internal combustion engine having a lubricating oil feeding system therefor including an oil sump and an oil pump in the crankcase of said engine: a starter motor arranged for selective driving connection with said internal combustion engine to start the latter, an oil reservoir arranged within said crankcase in spaced relationship to said oil sump, conduit means leading from said pump to said reservoir to feed oil under pressure thereto, said reservoir being open at the top thereof for releasing excess oil back into said sump, further conduit means arranged to convey oil from said reservoir to said starter motor, and oil pump means drivingly connected with said starter motor and operable independently of said pump, said pump means being arranged within said conduit means for feeding oil from said reservoir to said starter motor independently of a flow of lubricating oil through said lubricating oil feeding system.

3. In combination with an internal combustion engine having a lubricating oil feeding system therefor including an oil sump: a starter motor arranged for selective driving connection with said internal combustion engine to start the latter, said starter motor having inlet means for taking in a fuel-oil mixture, a carburetor spaced from said inlet means for cooperation with said starter motor, pipe means connecting said carburetor with said inlet means, an oil reservoir separate from said oil sump and arranged to be fed with oil by said oil feeding system, conduit means communicating with said reservoir and leading into said pipe means at a point intermediate said carburetor and said starter motor, and oil pump means provided in said conduit means and arranged to feed oil from said reservoir to said starter motor independently of a flow of lubricating oil through said lubricating oil feeding system.

4-. In combination with an internal combustion engine having a lubricating oil feeding system therefor including an oil sump: a starter motor arranged for selective driving connection with said internal combustion engine to start the latter, an oil reservoir separate from said oil sump and arranged to be fed with oil by said oil feeding system, an oil pump independent of the operation of said internal combustion engine and arranged for cooperation with said starter motor, first conduit means leading from said reservoir to the suction side of said pump, and second conduit means leading from the delivery side of said pump directly to points to be lubricated of said starter motor.

References Cited in the file of this patent UNITED STATES PATENTS 1,331,765 Heinze Feb. 24, 1920 FOREIGN PATENTS 667,001 Germany Nov. 3, 1938 

